1. Field of the Invention
This invention relates to a device for generating a teaching model applied to a method of detecting the position and posture of an object through pattern matching. More particularly, the present invention relates to a device for generating a teaching model for making it possible to detect an object regardless of three-dimensional variations in position and posture of the object for detection.
2. Description of the Prior Art
There is provided a well-known method and device for detecting the position and posture of an object set on a plane by storing a two-dimensional image of the object for detection as a teaching model prior to pattern matching of the teaching model with image data produced by means of taking an image of the object with an image pickup means such as a camera. The above method and device for detecting the object is applied to conveyance or like jobs of machine parts and articles or like workpieces grasped with a robot to a predetermined position in an automatic mode.
However, picking-out of an individual workpiece from a pile of disordered same-shaped workpieces or a set of same-shaped workpieces housed within a predetermined range in any three-dimensionally different position and posture is not suited for the robot, and therefore, requires manual operation. In the case of allowing the robot to pick out such an individual workpiece, there is the need for the manual operation of picking out the workpieces one by one from the pile of disordered workpieces for reoriented alignment such that the robot may pick out the individual workpiece directly.
For allowing the robot to grasp each workpiece for picking out from a large number of same-shaped workpieces piled up disorderly or housed within the predetermined range in any three-dimensionally different position and posture, it is necessary for the robot to recognize the position and posture (direction) of each of the above workpieces.
In this connection, a device for detecting the three-dimensional position and posture (direction) of the individual workpiece among the workpieces has been developed. This device performs the following operations.
(1) To produce image data in advance by taking an image of one of same-shaped workpieces for detection with a camera from different directions
(2) To store a plurality of teaching models based on the produced image data, together with the relative position and posture of each teaching model to the workpiece
(3) To select a teaching model of a high matching value by carrying out pattern matching of each teaching model with image data produced by taking an image of the piled same-shaped workpieces with the camera
(4) For this selected teaching model to detect the position and posture (direction) of the target workpiece for detection to the selected teaching model on the basis of the relative position and posture of each teaching model to the workpiece, stored in the above operation (2).
The above device requires a plurality of teaching models generated by taking the image of the workpiece from the plurality of directions as shown in the above operation (1).